Page "Forty-seven Ronin" Paragraph 57

Ōishi, from the perspective of bushido, was too obsessed with success.

He conceived his convoluted plan to ensure they would succeed at killing Kira, which is not a proper concern in a samurai: the important thing was not the death of Kira, but for the former samurai of Asano to show outstanding courage and determination in an all-out attack against the Kira house, thus winning everlasting honor for their dead master.

Even if they failed to kill Kira, even if they all perished, it wouldn't have mattered, as victory and defeat have no importance in bushido.

By waiting a year they improved their chances of success but risked dishonoring the name of their clan, the worst sin a samurai can commit.

This is why Yamamoto and others claim that the tale of the Forty-seven Ronin is a good story of revenge — but by no means a story of bushido.